Boom actuating mechanism for mechanical shovels



c. J. DAVIS BOOM ACTUATING MECHANISM FOR MECHANICAL SHOVELS April 21, 1959 2 snags-s eet 1 Filed April 9, 1956 CHARLES J. DAVIS INVEN TOR.

ATTORN EY A ril 21, 1959 c. J. DAVIS 2,833,067

BOOM ACTUATING MECHANISM FOR MECHANICAL SHOVELS Filed April 9, 1956 2 Sheets-Sheet 2 OHARLEs J. DAVIS INVENTOR.

ATTO RN EY United States Patent BOOM ACTUATING MECHANISM FOR NHECHANICAL SHOVELS Charles J. Davis, Wichita, Kans., assignor, by mesne assignments, to Massey-Ferguson Inc., a corporation of Maryland Application April 9, 1956, Serial No. 577,144

4 Claims. (Cl. 212-66) This invention relates generally to boom actuating devices and pertains more particularly to apparatus for permitting a mechanical shovel or the like to be moved through an optimum angle in performing desired functions.

To illustrate the utility of the invention it may be explained that in performing earth moving operations with a mechanical shovel the shovel apparatus is usually associated with some sort of vehicle by which the shovel may be advanced to new locations as progres is made in conducting the operations. Elaborate, complicated and expensive equipment has been devised for moving mechanical shovels through arcs as great as 360", such as in large self-powered rotary shovels where the motive means is located on the same swivel platform supporting the shovel mechanism. However, a real need exists for a mechanism that will have suificient arcuate movement to conduct all normal shoveling operations, yet be sufficiently simple so that it can be constructed quite inexpensively, thereby encouraging its use as an attachment for tractors and the like.

Accordingly, one important object of the present invention is to provide a boom actuating mechanism for mechanical shovels having such versatility that it can be utilized in conjunction with vehicles of conventional construction such as tractors equipped with hydraulic pumping systems. More specifically, it is an aim of the invention to provide an actuating mechanism of the foregoing character that will permit the boom of a mechanical shovel to be swung through an arc of 90 to either side of a central position, thereby allowing the shovel to be loaded at one side of the vehicle, as when digging a roadside ditch extending parallel to the vehicle, and then swung to the other side of its central or neutral position to dump the load. Conversely, the invention also permits the vehicle to straddle a ditch being dug with the unloading taking place at one side, the invention enabling the removed earth to be deposited at vantage points laterally spaced from the ditch itself through the full utilization of the shovels reach.

While the invention, as above mentioned, envisages the achieving of a full 90 swing to either side, another object of the invention is to permit the operator to select the particular side that affords the greater convenience. In other words, provision is made for adjusting the boom actuating mechanism for a 90 movement relative to either side, thereby permitting the vehicle and the attached shovel apparatus to be maneuvered into positions where encountered obstacles dictate that the work be performed from a particular side. For instance, it is possible to conduct digging operations in crowded areas where trees, boulders, graves, or buildings would otherwise hamper or prevent such digging.

A further object of the invention is to provide a boom actuating mechanism that can be readily stabilized where the terrain is uneven or hilly, thereby preventing the unit from tipping over on slopes and at the same time permitting the operator to dig plumb sidewalls.

The invention, together with other objects attending its production, will be more clearly understood when the following description is read in connection with the accompanying drawings, in which:

Figure 1 is a perspective view of the boom actuating mechanism exemplifying the invention;

Figure 2 is another perspective view of the invention, resembling somewhat the view depicted in Figure 1 but taken at a slightly different angle with portions of the structure broken away in order to illustrate more clearly certain features;

Figure 3 is a plan view, partly in section, illustrating the mechanism in a position adjusted for a swing on one side, as depicted in solid outline, and a lesser angle on the other side, as indicated by the dotted position;

Figure 4 is a view similar to Figure 3 but with the mechanism adjusted for equal swings to either side as dented by the solid and dotted line positions, and

Figure 5 is a side elevational view of the mechanism with parts thereof in section, the view being taken generally in the direction of line 5--5 of Figure 2 but with certain parts removed for purposes of clarity.

Referring now in detail to the drawings the boom actuating mechanism is designated in its entirety by the letter A. Inasmuch as it is intended that the actuating mechanism be employed in conjunction with tractors and the like equipped with hydraulic pressure systems, such a vehicle is pictured in phantom outline in Figure 1 and is denoted generally by the letter B.

The mechanism A includes a generally rectangular frame comprised of upper and lower cross beams 10 and 12, respectively, welded or otherwise secured to vertical studs 14 and 16. The frame is preferably reinforced with inclined struts 18 and various gusset plates 20, 22 located at the upper and lower corners of the frame. By selecting hollow vertical studs 14 and 16 with a rectangular crosssection, a pair of stabilizing legs 24 may be telescopically received therein having feet 26 at their lower ends. While not shown, these legs 24 can be individually extended or retracted to the degree necessary to maintain the frame structure substantially level, even though the boom actuating mechanism might be used on the side of a hill or where the ground is extremely uneven. In practice these legs will normally be hydraulically actuated, although a mechanical jack arrangement might serve the purpose in some instances.

Secured to the upper and lower cross beams 10, 12 and extending therefrom in a cantilever fashion are what might be termed split web I-beams 28, 30. By reason of the split or double web construction of these relatively short beams 28, 30 they serve as a support means for thev ends of a king post assembly via which the required swivel action is achieved. As can be seen from Figure 5, the king post assembly includes a vertical rod 32 equipped with oppositely directed ears 34, 36 for attachment to the beams 28, 30 through the agency of a pair of pins or bolts 38. Encircling sections of the rod 32 near its opposite ends are ball bearings 40, 42, these bearings being disposed within a cylindrical casing or column 44. Close inspection of Figure 5 will reveal the presence of an internal collar 46 secured to the inner wall of the casing 44 and resting upon the upper race of the bearing 42. The lower race of the bearing 42 is supported upon a circular flange 48 integral with the rod 32 which in turn rests upon the top side of the lower I-beam 30. In this way, the casing or column 44 is permitted to rotate, yet the load shouldered by said casing is effectively transferred to the frame via the two I-beams 28, 30, the lower one taking most of this load as is readily understandable.

Coming now to a very important part of the invention, it is to be noted that a trio of vertically spaced plate members 50 have their intermediate portions circumscribed about the column 44 and welded thereto so as to be movable in unison with said column or casing. Each of these plate members is fan or sector-shaped, being wider at their free ends so as to provide sufficient area for the location of three angularly spaced apertures 52. The other ends of the various plate members 50 merge together in a vertical direction but are forked so as to provide a clevis support 53 for a boom 54. A pin 56 permits the boom to be pivotally raised and lowered, where. as the bearings 40 and 42 allow rotation of the boom about a vertical axis. For the purpose of elevating the boom 54, another clevis support 58 is employed, having pivotally attached thereto, by means of a pin 60, a hydraulic cylinder 62. The hydraulic cylinder 62 has reciprocally mounted therein a piston (not shown), the rod of which connects to the boom 54 at a remote, mechanically advantageous point.

Returning now to the specific role played by the plate members 50, it is to be explained that any vertically aligned group of the apertures 52 may be selected for the pivotal attachment of the adjacent ends of a pair of piston rods' 64 and 66, a bolt or threaded pin 68 affording such a connection in conjunction with a removable nut mem ber' 70. The pistons to which the rods 64, 66 are connected are housed in hydraulic cylinders 72 and 74, these cylinders receiving fluid under pressure via flexible hoses 75 from a pumping system on the tractor B. The bydraulic cylinders 72 and 74 are equipped with cars 76 adapted to be pivotally pinned to clevis joints 78 and 80 fixedly mounted on the studs 14 and 16. The hydraulic cylinders 72 and 74 therefore function as actuating devices for the rotation of the boom 54 through the medium of the plate members 50.

From an examination of Figures 3 and 4 it can be disc'erned that the middle aperture of the apertures 52 is situated in direct alignment with the boom 54, whereas the other apertures are disposed in an offset manner. By virtue of the strategic location of these three apertures 52 the operator is enabled to select the aperture best suiting the operation at hand. For instance, if the boom 54 supports a mechanical shovel and it is desired to excavate in a direction paralleling the direction in which the tractor B is headed, then the piston rods 64 and 66 may be connected by means of the pin 68 to the particular aperture pictured in Figure 3. As already mentioned there are three vertically arranged plate members 50, and the spacing between these plate members produces what might be referred to as a double clevis (see Figure with the end of the rod 66 being pivotally pinned between, say, the middle plate member and the uppermost one, and the rod 68 between said middle plate member and the lowermost one. The exploded arrangement shown in Figure 2 with portions of the plates 50 removed is intended to illustrate this mode of fastening.

With the rods 64 and 66 connected as shown in Figure 3, the boom 54 can be swung into a parallel relationship with the frame comprised of the members 10, 12, 14 and 16. This would place the upper or free end of the boom on the extreme right side of the tractor B as viewed in Figure 1. No interference is encountered from any of the elements making up the king post owing to the offset relation of this particular aperture 52 selected with respeot to a line extending from the boom 54 through the rod 40 about which the swivel action takes place.

Forcing of the piston rod 66 outwardly from its cylinder 74 by fluid pressure with the concomitant retraction of the piston rod 64 into its cylinder 72 will result in the boom 54 swinging through an are from its solid line location into its dotted line position of Figure 3. This arcuate swing is in the neighborhood of 140 and of course includes a swing through 90, a position in which the boom is normal to the general plane of the frame members 10, 12, 14 and 16.

However, with the connection of the rods 64 and 66 as set forth in Figure 3, the extreme left side of the tractor B would not be reached, being capable in this instance of going about 50 in this direction. Provision is made, though, for establishing a parallel relationship with the frame whereby this other side can be reached. This is done by merely removing the pin 68 and relocating it into the aperture 52 lying on the other side of the middle aperture, i.e. the one on the other side of the aperture in alignment with the boom 54. Having so relocated the pin and the adjacent ends of the piston rods 64 and 66, it is believed readily apparent that the boom 54 will be displaced 180 from the solid line position shown in Figure 3.

With the foregoing operation in mind it is thought evident that use of the middle aperture will produce a compromise between the two side extremes. However, resort to Figure 4 will clearly demonstrate the realization of this compromise, for here the solid line position of the boom forms an angle of about 70 with the normal or central position that the boom may assume, and the dotted line position represents the same swing on the other side of the normal.

Although the description up to this point has been silent as to the particular manner in which the boom actuating mechanism A is retained in a fixedly upright condition, it is believed obvious that suitable tie rods may be detaohably secured to each side of the tractor B or whatever vehicle is selected for use with the exemplified mechanism.

Having described the invention with sufiicient clarity to enable those familiar with this art to construct and use it, I claim:

1. In a mechanical shovel, in combination, a frame having its structural elements lying substantially in a vertical plane, a pair of vertically spaced cantilever members projecting perpendicularly from said frame, a vertical rod having its upper and lower ends attached to said cantilever members, a cylindrical column circumscribing said rod, bearing means intermediate said rod and column so as to render said column rotatable about said rod, a boom mounted on said column for rotation therewith, asectorshaped plate mounted on said column and extending in opposite direction with respect to said boom, said plate being provided with a first aperture in alignment with said boom and additional apertures angularly spaced from said first aperture on either side thereof, and a pair of piston means having their opposite ends pivotally anchored to the ends of said frame and their adjacent ends pivotally pinned to one of said apertures, the selected connection with said first aperture providing for rotation of said boom from a central normal position relative to said frame through an are less than to either side and connection with either of said additional apertures providing for rotation of the boom from a normal position.

relative to said frame through an arc of 90 to a parallel side position with respect to the frame with the particular side depending upon which additional aperture is utilized.

2. In a mechanical shovel as defined in claim 1 in which two additional sector-shaped plates are employed spaced vertically with respect to the first mentioned plate to form a double clevis for the reception therebetween of the adjacent ends of said respective piston means, and a pin extending vertically through all three of said sectorshaped plates and said adjacent piston ends.

3. In a mechanical shovel, in combination: a generally planar upright frame including spaced upper and lower cross members; an upright boom supporting post having its upper and lower ends pivotally supported by the respective frame cross members to afford swinging movement of the boom about an upright pivot axis; a boom swinging lever having its inner end rigidly secured to said post and its outer free end projecting radially outward with respect to the pivot axis of the post on that side of the post substantially opposite the point of boom attachment, the outer free end of the lever being in the form of three vertically spaced similarly oriented rigid members; a plurality of sets of vertically aligned circumferentially spaced apertures in said members near the peripheries thereof; a pair of opposed extensible and retractable hydraulic motor units for rotating the boom supporting post, located on opposite sides thereof; means pivotally connecting the outer end of each motor unit to the frame on individual vertical axes; and means pivotally connecting the inner end of each motor unit to the outer end of the boom swinging lever on a common vertical axis, the respective inner ends of the motor units being located on opposite sides of the middle one of said members.

4. In a mechanical shovel as described in claim 3 in which the means for pivotally connecting the inner ends of the respective motor units to the boom swinging lever is a pivot pin passing through a selected set of vertically aligned apertures in the spaced members of the lever and through an aperture in each inner end of each motor unit, the inner end of one motor unit being positioned between the intermediate and lowermost member of the lever, and the inner end of the other motor unit being positioned between the intermediate and the uppermost member of the lever, whereby a changing of the said pivot pin to a different set of vertically aligned apertures in the members varies the orientation of the are through which the boom may be swung to either side of a central or neutral position.

References Cited in the file of this patent UNITED STATES PATENTS 1,553,063 Bedgood Sept. 8, 1925 2,528,985 Wunsch Nov. 7, 1950 2,672,990 Sundin Mar. 23, 1954 2,674,385 Stauth Apr. 6, 1954 2,702,137 Ives Feb. 15, 1955 

